M3 Screw Knob

thingiverse

I've been working on a Drawing Robot (https://www.thingiverse.com/thing:2349232) and encountered difficulties getting the thumbscrew knob to function properly for me. The hole for the nut was too small, which might be a printing issue, so I decided to create my own design using OpenSCAD. All aspects are customizable, and hopefully the variables are well-documented enough if anyone needs to make adjustments. I used a Nylok M3 nut to secure mine, requiring a deeper recess, but there are clues in the comments if you prefer to use standard nuts. The depth of the knob is calculated - depth of the screw head plus depth of the nut plus 3mm. This design is offered with the hope that it may be useful to someone - I won't be developing it any further. A minor update fixed a silly piece of OpenSCAD coding - it didn't affect the print, but the bad code annoyed me.